(Slip Opinion) OCTOBER TERM, 2013 1 

Syllabus 

NOTE: Where it is feasible, a syllabus (headnote) will be released, as is

being done in connection with this case, at the time the opinion is issued.

The syllabus constitutes no part of the opinion of the Court but has been

prepared by the Reporter of Decisions for the convenience of the reader. 

See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337. 

SUPREME COURT OF THE UNITED STATES 

Syllabus 

LIMELIGHT NETWORKS, INC. v. AKAMAI 

TECHNOLOGIES, INC., ET AL. 

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR 

THE FEDERAL CIRCUIT 

No. 12–786. Argued April 30, 2014—Decided June 2, 2014 

Akamai Technologies, Inc., a respondent here, is the exclusive licensee

of a patent that claims a method of delivering electronic data using a 

content delivery network (CDN). Petitioner, Limelight Networks, 

Inc., also operates a CDN and carries out several of the steps claimed

in the patent, but its customers, rather than Limelight itself, perform 

a step of the patent known as “tagging.” Under Federal Circuit case 

law, liability for direct infringement under 35 U. S. C. §271(a) requires performance of all steps of a method patent to be attributable

to a single party. This position was most recently refined in Muniauction, Inc. v. Thomson Corp., 532 F. 3d 1318. The District Court 

concluded that Limelight could not have directly infringed the patent 

at issue because performance of the tagging step could not be attributed to it. The en banc Federal Circuit reversed, holding that a 

defendant who performed some steps of a method patent and encouraged others to perform the rest could be liable for inducement of infringement even if no one was liable for direct infringement. The en 

banc court concluded that the evidence could support liability for

Limelight on an inducement theory and remanded for further proceedings. 

Held: A defendant is not liable for inducing infringement under §271(b)

when no one has directly infringed under §271(a) or any other statutory provision. Pp. 4–11.

(a) Liability for inducement must be predicated on direct infringement. Aro Mfg. Co. v. Convertible Top Replacement Co., 365 U. S. 

336, 341. Assuming that Muniauction’s holding is correct, respondents’ method has not been infringed because the performance of all of

its steps is not attributable to any one person. Since direct infringe-
 

 

2 LIMELIGHT NETWORKS, INC. v. AKAMAI 

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Syllabus
 

ment has not occurred, there can be no inducement of infringement

under §271(b). The Federal Circuit’s contrary view would deprive 

§271(b) of ascertainable standards and require the courts to develop

two parallel bodies of infringement law. This Court’s reading of

§271(b) is reinforced by §271(f)(1), which illustrates that Congress

knows how to impose inducement liability predicated on noninfringing conduct when it wishes to do so. The notion that conduct 

which would be infringing in altered circumstances can form the basis for contributory infringement has been rejected, see Deepsouth 

Packing Co. v. Laitram Corp., 406 U. S. 518, 526–527, and there is no 

reason to apply a different rule for inducement. Pp. 4–7.

(b) Respondents claim that principles from tort law and criminal 

aiding and abetting doctrine, as well as patent law principles in existence before the 1952 Patent Act, support the Federal Circuit’s

reading of the statute, but their arguments are unpersuasive.

Though a would-be infringer could evade liability by dividing performance of a method patent’s steps with another whose conduct cannot 

be attributed to the defendant, this is merely a result of the Federal 

Circuit’s interpretation of §271(a), and a desire to avoid this consequence does not justify fundamentally altering the rules of inducement liability clearly required by the Patent Act’s text and structure.

Pp. 8–10.

(c) Because the question presented here is clearly focused on 

§271(b) and presupposes that Limelight has not committed direct infringement under §271(a), the Court declines to address whether the 

Federal Circuit’s decision in Muniauction is correct. P. 10. 

692 F. 3d 1301, reversed and remanded. 

ALITO, J., delivered the opinion for a unanimous Court. 
 

 

_________________ 

_________________ 

 

 

 

Cite as: 572 U. S. ____ (2014) 1 

Opinion of the Court 

NOTICE: This opinion is subject to formal revision before publication in the

preliminary print of the United States Reports. Readers are requested to

notify the Reporter of Decisions, Supreme Court of the United States, Washington, D. C. 20543, of any typographical or other formal errors, in order

that corrections may be made before the preliminary print goes to press. 

SUPREME COURT OF THE UNITED STATES 

No. 12–786 

LIMELIGHT NETWORKS, INC., PETITIONER v.
 

AKAMAI TECHNOLOGIES, INC., ET AL. 

ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

APPEALS FOR THE FEDERAL CIRCUIT
 

[June 2, 2014]

 JUSTICE ALITO delivered the opinion of the Court. 

This case presents the question whether a defendant 

may be liable for inducing infringement of a patent under 

35 U. S. C. §271(b) when no one has directly infringed the

patent under §271(a) or any other statutory provision.

The statutory text and structure and our prior case law 

require that we answer this question in the negative. We 

accordingly reverse the Federal Circuit, which reached the

opposite conclusion. 

I 

A 

Respondent the Massachusetts Institute of Technology

is the assignee of U. S. Patent No. 6,108,703 (’703 patent), 

which claims a method of delivering electronic data using

a “content delivery network,” or “CDN.” Respondent

Akamai Technologies, Inc., is the exclusive licensee.

Akamai maintains many servers distributed in various 

locations. Proprietors of Web sites, known as “content 

providers,” contract with Akamai to deliver their Web 

sites’ content to individual Internet users. The ’703 patent

provides for the designation of certain components of a 
2 LIMELIGHT NETWORKS, INC. v. AKAMAI 

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Opinion of the Court 

content provider’s Web site (often large files, such as video

or music files) to be stored on Akamai’s servers and accessed from those servers by Internet users. The process

of designating components to be stored on Akamai’s servers is known as “tagging.” By “aggregat[ing] the data 

demands of multiple content providers with differing peak

usage patterns and serv[ing] that content from multiple 

servers in multiple locations,” 614 F. Supp. 2d 90, 96

(Mass. 2009), as well as by delivering content from servers

located in the same geographic area as the users who are

attempting to access it, Akamai is able to increase the 

speed with which Internet users access the content of its

customers’ Web sites. 

Petitioner Limelight Networks, Inc., also operates a 

CDN and carries out several of the steps claimed in the 

’703 patent. But instead of tagging those components of its

customers’ Web sites that it intends to store on its servers 

(a step included in the ’703 patent), Limelight requires its

customers to do their own tagging.1 Respondents claim

that Limelight “provides instructions and offers technical 

assistance” to its customers regarding how to tag, 629 

F. 3d 1311, 1321 (CA Fed. 2010), but the record is undisputed that Limelight does not tag the components to be

stored on its servers. 

B 

In 2006, respondents sued Limelight in the United 

States District Court for the District of Massachusetts, 

claiming patent infringement. The case was tried to a 

jury, which found that Limelight had committed infringement and awarded more than $40 million in damages. 

Respondents’ victory was short-lived, however. After 

—————— 

1 In its brief, Limelight disputes whether its customers actually “tag”

within the meaning of the patent. Brief for Petitioner 7, n. 4. We 

assume arguendo that Limelight’s customers do in fact “tag” within the 

patent’s meaning. 
Cite as: 572 U. S. ____ (2014) 3 

Opinion of the Court 

the jury returned its verdict, the Federal Circuit decided 

Muniauction, Inc. v. Thomson Corp., 532 F. 3d 1318 

(2008). In that case the Court of Appeals rejected a claim

that the defendant’s method, involving bidding on financial instruments using a computer system, directly infringed the plaintiff ’s patent. The defendant performed 

some of the steps of the patented method, and its customers, to whom the defendant gave access to its system along 

with instructions on the use of the system, performed the 

remaining steps. The court started from “the proposition 

that direct infringement requires a single party to perform

every step of a claimed method.” Id., at 1329. This requirement is satisfied even though the steps are actually

undertaken by multiple parties, the court explained, if a

single defendant “exercises ‘control or direction’ over the 

entire process such that every step is attributable to the 

controlling party.” Ibid. The court held that the defendant in Muniauction was not liable for direct infringement 

because it did not exercise control or direction over its 

customers’ performance of those steps of the patent that 

the defendant itself did not perform. Id., at 1330. 

In light of Muniauction, Limelight moved for reconsideration of its earlier motion for judgment as a matter of 

law, which the District Court had denied. The District 

Court granted the motion, concluding that Muniauction 

precluded a finding of direct infringement under §271(a) 

because infringement of the ’703 patent required tagging

and Limelight does not control or direct its customers’

tagging. A panel of the Federal Circuit affirmed, explaining that a defendant that does not itself undertake all of a 

patent’s steps can be liable for direct infringement only

“when there is an agency relationship between the parties

who perform the method steps or when one party is contractually obligated to the other to perform the steps.” 629 

F. 3d, at 1320. Since neither of these conditions was met 

in the present case, the Federal Circuit panel held that 
 

 

4 LIMELIGHT NETWORKS, INC. v. AKAMAI 

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Opinion of the Court 

Limelight could not be held liable for direct infringement.2 

Ibid. 

The Federal Circuit granted en banc review and reversed. The en banc court found it unnecessary to revisit 

its §271(a) direct infringement case law. Instead, it concluded that the “evidence could support a judgment in

[respondents’] favor on a theory of induced infringement”

under §271(b). 692 F. 3d 1301, 1319 (2012) (per curiam).

This was true, the court explained, because §271(b) liability arises when a defendant carries out some steps constituting a method patent and encourages others to carry out

the remaining steps—even if no one would be liable as a 

direct infringer in such circumstances, because those who 

performed the remaining steps did not act as agents of, or 

under the direction or control of, the defendant. The 

Court of Appeals did not dispute that “there can be no 

indirect infringement without direct infringement,” id., at 

1308, but it explained that “[r]equiring proof that there

has been direct infringement . . . is not the same as requiring proof that a single party would be liable as a direct 

infringer,” id., at 1308–1309 (emphasis deleted). Judge

Newman and Judge Linn both dissented (with the latter

joined by Judges Dyk, Prost, and O’Malley).

Limelight sought certiorari, which we granted. 571 

U. S. ___ (2014). 

II
 

A 

Neither the Federal Circuit, see 692 F. 3d, at 1308, nor 

respondents, see Tr. of Oral Arg. 44, dispute the proposition that liability for inducement must be predicated on 

—————— 

2The panel noted that Limelight’s contracts instruct its customers to 

tag the components they wish to be stored on Limelight’s CDN, but

concluded that, because these contracts did not give Limelight control 

over its customers, the customers’ tagging could not be attributed to 

Limelight. See 629 F. 3d, at 1321. 
Cite as: 572 U. S. ____ (2014) 5 

Opinion of the Court 

direct infringement. This is for good reason, as our case 

law leaves no doubt that inducement liability may arise

“if, but only if, [there is] . . . direct infringement.” Aro Mfg. 

Co. v. Convertible Top Replacement Co., 365 U. S 336, 341 

(1961) (emphasis deleted).3 

One might think that this simple truth is enough to 

dispose of this appeal. But the Federal Circuit reasoned 

that a defendant can be liable for inducing infringement 

under §271(b) even if no one has committed direct infringement within the terms of §271(a) (or any other provision of the patent laws), because direct infringement can

exist independently of a violation of these statutory provisions. See 692 F. 3d, at 1314. 

The Federal Circuit’s analysis fundamentally misunderstands what it means to infringe a method patent. A 

method patent claims a number of steps; under this 

Court’s case law, the patent is not infringed unless all the 

steps are carried out. See, e.g., Aro, supra, at 344 (a “patent covers only the totality of the elements in the claim

and . . . no element, separately viewed, is within the 

grant”). This principle follows ineluctably from what a

patent is: the conferral of rights in a particular claimed set 

of elements. “Each element contained in a patent claim is

deemed material to defining the scope of the patented

invention,” Warner-Jenkinson Co. v. Hilton Davis Chemical Co., 520 U. S. 17, 29 (1997), and a patentee’s rights 

extend only to the claimed combination of elements, and 

no further. 

The Federal Circuit held in Muniauction that a method’s steps have not all been performed as claimed by the 

patent unless they are all attributable to the same de-

—————— 

3 Aro addressed contributory infringement under §271(c), rather than

inducement of infringement under §271(b), but we see no basis to 

distinguish for these purposes between the two, which after all spring 

from common stock. See Global-Tech Appliances, Inc. v. SEB S. A., 563 

U. S. ___, ___ (2011) (slip op., at 8). 
6 LIMELIGHT NETWORKS, INC. v. AKAMAI 

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Opinion of the Court 

fendant, either because the defendant actually performed 

those steps or because he directed or controlled others who

performed them. See 532 F. 3d, at 1329–1330. Assuming

without deciding that the Federal Circuit’s holding in 

Muniauction is correct, there has simply been no infringement of the method in which respondents have

staked out an interest, because the performance of all the

patent’s steps is not attributable to any one person. And, 

as both the Federal Circuit and respondents admit, where 

there has been no direct infringement, there can be no

inducement of infringement under §271(b).

The Federal Circuit’s contrary view would deprive

§271(b) of ascertainable standards. If a defendant can be 

held liable under §271(b) for inducing conduct that does 

not constitute infringement, then how can a court assess

when a patent holder’s rights have been invaded? What if 

a defendant pays another to perform just one step of a 12-

step process, and no one performs the other steps, but that 

one step can be viewed as the most important step in the

process? In that case the defendant has not encouraged 

infringement, but no principled reason prevents him from 

being held liable for inducement under the Federal Circuit’s reasoning, which permits inducement liability when

fewer than all of a method’s steps have been performed

within the meaning of the patent. The decision below 

would require the courts to develop two parallel bodies of

infringement law: one for liability for direct infringement, 

and one for liability for inducement. 

Section 271(f)(1) reinforces our reading of §271(b). That 

subsection imposes liability on a party who “supplies or 

causes to be supplied in or from the United States all or a 

substantial portion of the components of a patented invention . . . in such manner as to actively induce the combination of such components outside of the United States in a

manner that would infringe the patent if such combination 

occurred within the United States” (emphasis added). As 
Cite as: 572 U. S. ____ (2014) 7 

Opinion of the Court 

this provision illustrates, when Congress wishes to impose 

liability for inducing activity that does not itself constitute 

direct infringement, it knows precisely how to do so. The 

courts should not create liability for inducement of noninfringing conduct where Congress has elected not to 

extend that concept.

The Federal Circuit seems to have adopted the view that

Limelight induced infringement on the theory that the

steps that Limelight and its customers perform would 

infringe the ’703 patent if all the steps were performed by 

the same person. But we have already rejected the notion

that conduct which would be infringing in altered circumstances can form the basis for contributory infringement,

and we see no reason to apply a different rule for inducement. In Deepsouth Packing Co. v. Laitram Corp., 406 

U. S. 518 (1972), a manufacturer produced components of 

a patented machine and then exported those components 

overseas to be assembled by its foreign customers.4 (The

assembly by the foreign customers did not violate U. S. 

patent laws.) In both Deepsouth and this case, the conduct 

that the defendant induced or contributed to would have 

been infringing if committed in altered circumstances: in 

Deepsouth if the machines had been assembled in the 

United States, see id., at 526, and in this case if performance of all of the claimed steps had been attributable to 

the same person. In Deepsouth, we rejected the possibility

of contributory infringement because the machines had 

not been assembled in the United States, and direct infringement had consequently never occurred. See id., at 

526–527. Similarly, in this case, performance of all the 

claimed steps cannot be attributed to a single person, so 

direct infringement never occurred. Limelight cannot be

liable for inducing infringement that never came to pass. 

—————— 

4Section 271(f) now prohibits the exporter’s conduct at issue in 

Deepsouth. 
8 LIMELIGHT NETWORKS, INC. v. AKAMAI 

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Opinion of the Court 

B 

Respondents’ arguments in support of the Federal Circuit’s reading of the statute are unpersuasive. First, 

respondents note that tort law imposes liability on a defendant who harms another through a third party, even if 

that third party would not himself be liable, and respondents contend that, given the background tort principles 

against which the Patent Act of 1952 was enacted, it

should not matter that no one is liable for direct infringement in this case. But the reason Limelight could not 

have induced infringement under §271(b) is not that no 

third party is liable for direct infringement; the problem,

instead, is that no direct infringement was committed. 

Muniauction (which, again, we assume to be correct)

instructs that a method patent is not directly infringed—

and the patentee’s interest is thus not violated—unless a

single actor can be held responsible for the performance of 

all steps of the patent. Because Limelight did not undertake all steps of the ’703 patent and cannot otherwise be 

held responsible for all those steps, respondents’ rights

have not been violated. Unsurprisingly, respondents point 

us to no tort case in which liability was imposed because a 

defendant caused an innocent third party to undertake

action that did not violate the plaintiff ’s legal rights.

In a related argument, respondents contend that, at

tort, liability sometimes attaches where two or more defendants inflict injury, even if each defendant’s conduct,

standing alone, would not be actionable. See W. Keeton, 

D. Dobbs, R. Keeton, & D. Owen, Prosser and Keeton on 

Torts §52, p. 354 (5th ed. 1984) (multiple defendants who 

each add negligible impurities to stream liable if aggregate impurities cause harm). But the rationale for imposing liability in these circumstances is that the defendants 

collectively invaded the plaintiff ’s protected interests. See 

ibid. By contrast, under the Muniauction rule, respondents’ interests in the ’713 patent have not been invaded. 
Cite as: 572 U. S. ____ (2014) 9 

Opinion of the Court 

Second, respondents seek to analogize §271(b) to the 

federal aiding and abetting statute, 18 U. S. C. §2, and 

they argue that two parties who divide all the necessary 

elements of a crime between them are both guilty under 

§2. The analogy does not hold up. The aiding and abetting statute must be read “against its common-law background,” Standefer v. United States, 447 U. S. 10, 19 

(1980), and at common law two or more defendants, each

of whom committed an element of a crime, were liable as 

principals. See, e.g., 1 J. Bishop, Commentaries on the

Criminal Law §649, p. 392 (7th ed. 1882). While we have 

drawn on criminal law concepts in the past in interpreting

§271(b), see Global-Tech Appliances, Inc. v. SEB S. A., 563 

U. S. ___, ___ (2011) (slip op., at 10–12), we think it unlikely that Congress had this particular doctrine in mind 

when it enacted the Patent Act of 1952, given the doctrine’s inconsistency with the Act’s cornerstone principle

that patentees have a right only to the set of elements

claimed in their patents and nothing further.

Third, respondents contend that patent law principles

established before the enactment of the Patent Act demonstrate that a defendant that performs some steps of a

patent with the purpose of having its customers perform

the remaining steps is liable for inducing infringement. 

But here, too, the nature of the rights created by the Patent Act defeats the notion that Congress could have 

intended to permit inducement liability where there is no

underlying direct infringement. According to respondents,

their understanding of the pre-1952 doctrine casts doubt

on the Muniauction rule for direct infringement under

§271(a), on the ground that that rule has the indirect 

effect of preventing inducement liability where Congress

would have wanted it. But the possibility that the Federal

Circuit erred by too narrowly circumscribing the scope of 

§271(a) is no reason for this Court to err a second time by

misconstruing §271(b) to impose liability for inducing 
 

10 LIMELIGHT NETWORKS, INC. v. AKAMAI 

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Opinion of the Court 

infringement where no infringement has occurred.

Finally, respondents, like the Federal Circuit, criticize

our interpretation of §271(b) as permitting a would-be

infringer to evade liability by dividing performance of a 

method patent’s steps with another whom the defendant

neither directs nor controls. We acknowledge this concern. 

Any such anomaly, however, would result from the Federal Circuit’s interpretation of §271(a) in Muniauction. A 

desire to avoid Muniauction’s natural consequences does

not justify fundamentally altering the rules of inducement

liability that the text and structure of the Patent Act 

clearly require—an alteration that would result in its own 

serious and problematic consequences, namely, creating 

for §271(b) purposes some free-floating concept of “infringement” both untethered to the statutory text and

difficult for the lower courts to apply consistently. 

III 

Respondents ask us to review the merits of the Federal

Circuit’s Muniauction rule for direct infringement under 

§271(a). We decline to do so today. 

In the first place, the question presented is clearly

focused on §271(b), not §271(a). We granted certiorari on 

the following question: “Whether the Federal Circuit erred 

in holding that a defendant may be held liable for inducing 

patent infringement under 35 U. S. C. §271(b) even though

no one has committed direct infringement under §271(a).” 

Pet. for Cert. i. The question presupposes that Limelight 

has not committed direct infringement under §271(a).

And since the question on which we granted certiorari did 

not involve §271(a), petitioner did not address that important issue in its opening brief. Our decision on the

§271(b) question necessitates a remand to the Federal 

Circuit, and on remand, the Federal Circuit will have the 

opportunity to revisit the §271(a) question if it so chooses. 
Cite as: 572 U. S. ____ (2014) 11 

Opinion of the Court 

IV 

The judgment below is reversed, and the case is remanded for further proceedings consistent with this opinion. 

It is so ordered.